Saturday, February 06, 2010

An Illustration of Science's Neglect of Purpose as an Explanatory Factor with Regard to Almost Anything

Excerpted from:

Concerning an interview with David Albert. a professor of philosophy at Columbia University, whose research is mostly concerned with issues of the foundations of physics. Titles heading the interview were: Where Philosophy Meets Science and The Profound Violence of Time

It would of course help to understand the following commentary if the entire transcript of the interview with David Albert were to be read first, but there were just too many pages for me to copy here. In any case, I've added the relevant parts to which my comments were directed:

ROY NILES on February 5, 2010, 7:54 PM

Extremely interesting until we get to this part:
“Note that the set of events depicted by the movie being shown in reverse is just as much in accord with everything we believe about the laws governing collisions between billiard balls as is the movie being shown in the correct direction. That is, if you were shown a movie like this and asked to guess — just based on your familiarity with the laws of physics, just based on your familiarity with how billiard balls behave when they collide — if you were shown a film like this and asked to guess whether it was being shown forward or in reverse, you wouldn’t be able to tell. Physicists express this by saying that the laws governing collisions between billiard balls are symmetric under time reversal, okay? And what that means more concretely is — a law is said to be symmetric under time reversal if it’s the case that for any process which is in accord with that law, the same process going in reverse — that is, the same process as it would appear in a film going backwards — is also in accord with that law. So we say that the laws governing collisions between pairs of billiard balls are time-reversal symmetric. Good.”

Me: But this is not true in the sense that we actually would be able to tell. Because the balls originally lost some momentum – one before hitting the other, and then the second losing momentum until running out of room or energy. In a reverse of the filming, the balls would both visibly or measurably gain momentum.
So whatever law is governing collisions between pairs of billiard balls, it doesn’t seem to be the one of time-reversal symmetry.
I can’t help but think that somehow I have to be wrong about this, because I can’t imagine how, otherwise, everyone else in the know here would seem to have to be.

ROY NILES on February 6, 2010, 1:10 PM

But let me comment further relative to this part:
“Once again, it appears as if although the theory does an extremely good job of predicting the motions of elementary particles and so on and so forth, there’s got to be something wrong with it, okay, because we have — although we have very good, clear quantitative experience in the laboratory which bears out these fully time-reversal symmetric laws, at some point there’s got to be something wrong with them, because the world that we live in manifestly not even close to being time-reversal symmetric.”

Me: Because perhaps the world we live in has to contend with purposive behaviors of those forms of energetic activity we’ve designated as living. It’s the reversal of purposive behaviors that can’t be seen or envisioned as a symmetrical process.
I’d go further in proposing that nature’s laws are purposive, life-giving being within that purpose or not.
If so, time-reversal symmetry breaks down accordingly.
And if purposive, we don’t know why, not knowing why there had or have to be laws to begin with (assuming they had a beginning and weren’t always here). But we should know in any case that we can’t reverse, with any form of symmetry, the purposes to which those laws are put.

ROY NILES on February 6, 2010, 3:00 PM

And try reversing the film of these billiard shots and observe the time reversal symmetry.

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Addendum: More will be said about all this later, but for now, consider this: Laws have a use, so one could argue that usefulness is essential to their purpose. To reverse "time" would be to destroy that useful purpose - that sequential order in nature that these laws seem universally devised to regulate.
And so if what exists at any point in time results from a conversion of diverse forces, purposive or no, any symmetry expected to be found with a reversal of that conversion just wouldn't be there. The web of causation that would need to reverse itself so obediently is in the end as vast as the universe.